Glass containers may be coated for a variety of different purposes, including damage prevention, e.g., scratch and abrasion resistance, and strength retention. Such coatings may be applied to the glass containers at various points in the manufacturing process. For example, glass containers are conventionally coated with metal oxides, e.g., oxides of tin, titanium, vanadium, or zirconium, at the “hot end” of the annealing lehr, and then overcoated with protective organic coatings, e.g., polyurethane or polypropylene, at the “cold end” of the annealing lehr. Accordingly, these conventional coatings may be referred to as cold end or hot end coatings. U.S. Patents that illustrate coating processes of this type include U.S. Pat. Nos. 3,323,889; 3,407,085; 3,414,429; 3,418,154; 3,425,859; 3,445,269; 3,498,825; 3,554,787; and 3,598,632.
A general object of the present disclosure, in accordance with one aspect of the disclosure, is to provide a process for coating glass containers that can improve the strength of the glass containers.
The present disclosure embodies a number of aspects that can be implemented separately from or in combination with each other.
A process for forming a graphene coating on a glass container, in accordance with one aspect of the disclosure, includes: (a) applying a graphene coating composition in liquid phase to an exterior surface of the glass container to form a precursor coating thereon; and (b) curing the precursor coating to form a composite thin film of silica and graphene on the exterior surface of the glass container. The graphene coating composition includes a physical mixture of a graphene material and a siloxane polymer, but does not include a non-silane organic monomer or polymer.
In accordance with another aspect of the disclosure, there is provided a glass container that includes: a glass substrate that defines the shape of the container and provides the container with a closed base at an axial end of the container, a body extending axially from the base and being circumferentially closed, and an open mouth at another axial end of the glass container opposite the base; and a graphene coating formed on an exterior surface of the glass substrate. The graphene coating is a composite that includes a dispersed phase of graphene and a matrix phase of silica (SiO2) and is bonded to the exterior surface of the glass container through a plurality of siloxane bonds.